When scientists take clues found in rocks, fossils, and the surrounding area to learn about an animal’s life, we call this a

your answer is "the 1950's"

ionic bonds are two oppositely charged ions that attract. a sodium ion has a 1 positive charge; a chloride ion has a 1 negative charge. sodium and chloride have oppostive charged ions that attract which forms an ionic bond. a chemical bond formed when two atoms share electrons is called